Anorexia Nervosa: Causes, Behaviors, and Prevention

Introduction to Anorexia Nervosa

Anorexia nervosa is defined in the Gale Encyclopedia of Alternative Medicine as "an eating disorder characterized by unrealistic fear of weight gain, self-starvation, and conspicuous distortion of body image." The fourth edition of the Diagnostic and Statistical Manual of Mental Disorders (DSM-IV, 1994) defines two subtypes of anorexia nervosa: a restricting type, characterized by strict dieting and exercise without binge eating, and a binge-eating/purging type, marked by episodes of compulsive eating with or without self-induced vomiting and the use of laxatives or enemas. The DSM-IV defines a binge as a time-limited (usually under two hours) episode of compulsive eating in which the individual consumes a significantly larger amount of food than most people would eat under similar circumstances.

The incidence of eating disorders, especially anorexia, is increasing at a worrisome rate. During the past three decades, the prevalence has increased dramatically. Tenore reports an overall incidence of approximately five percent of the population of the United States.

Although eating disorders generally occur in adolescents, they are now seen much more often in children and adults, including the elderly. It was originally thought that only five percent of anorexics are male, but that estimate is being revised upward. The peak age range for onset of the disorder is 14 to 18 years, although there are patients who develop anorexia as late as their 40s. In the 1970s and 1980s, anorexia was regarded as a disorder of upper- and middle-class women, but that generalization is also changing. More recent studies indicate that anorexia is increasingly common among women of all races and social classes in the United States.

Biological and Psychological Risk Factors

Anorexia nervosa combines pathological thoughts and behaviors about food and weight with negative emotions concerning appearance, eating, and food. These thoughts, feelings, and behaviors lead to changes in body composition and functioning that are the direct result of starvation. Among adolescents, the illness severely affects physical, emotional, and social development. In addition, there is a fair amount of evidence suggesting that anorexia nervosa often co-occurs with other psychiatric disorders, including depression, anxiety disorders, and obsessive-compulsive disorder (Lock). This makes both diagnosing and treating anorexia nervosa a serious challenge.

It is important, therefore, to study and understand some of the causes of anorexia nervosa and its associated behaviors in order to provide help and support for the many people — especially adolescent girls — afflicted with this condition.

There is no single simple answer for the causes of anorexia. Some or all of the following factors could combine to produce starving, stuffing, and purging in a given individual. Biological factors are intertwined with psychological ones. Some personality types, such as obsessive-compulsive and sensitive-avoidant personalities, are more vulnerable to eating disorders. Anorexics are generally described as good children — eager to please, hardworking, and academically strong. Typically they are people-pleasers who seek approval and avoid conflict. It is thought that this striving for perfection leads to feelings of inadequacy and defectiveness, which in turn produce stress and anxiety. Eating disorders may then emerge as a way of masking or avoiding these stressful demands. People with a low tolerance for change have also seemed to turn to dieting and preoccupation with weight as a coping mechanism.

LoBuono reports that psychological risk factors for eating disorders include generalized anxiety and phobias, depression, obsessive-compulsive tendencies, and social phobia. The impulsive personality type, often seen in those who abuse drugs and alcohol, is associated with bulimic patients. A family history of disordered eating is also significant. Eating disorders are more common among those who are perfectionists, have low self-esteem, or are overly self-critical and consider themselves unsuccessful or ineffective in their everyday lives.

Family Dynamics and Childhood Trauma

Closely tied to psychological factors is the issue of body image and how satisfied a person is with his or her own appearance. This is greatly influenced by society's views on the ideal body. People who are convinced they need to lose weight will often diet rigorously, even when counselors have told them this is unnecessary. Dieting becomes an even greater problem because it alters body chemistry in ways that can prolong the disorder. So-called fad dieting can trigger a physiological binge-purge cycle: these diets restrict food intake, decreasing the body's metabolic rate. When people return to consuming normal amounts of food, it is now stored as fat rather than used as a source of nutrients. The resulting weight gain causes them to restrict their intake even further. Patients who strictly follow a low-fat eating plan may also unknowingly deprive themselves of necessary dietary fat, which can cause them to binge on large amounts of high-fat food to compensate. Genetics have also been implicated in predisposing certain individuals to anorexia nervosa.

The second group of factors that can result in eating disorders involves family dynamics. Some anorexia patients feel smothered by their families; others feel abandoned, misunderstood, or alone. Families of patients with eating disorders tend to share certain social characteristics — they generally do not handle conflict well and tend to struggle with interpersonal harmony. When children are subjected to their parents' high expectations of achievement and success, they may conceal their doubts, fears, anxieties, and perceived imperfections by manipulating their weight and food intake. Furthermore, parents who overvalue physical appearance or make critical comments — even in jest — about their children's bodies may unwittingly push those children toward eating disorders. The pressure need not come from the family alone; appearance-obsessed friends, partners, or peer groups can create similar harmful pressures.

A combination of family and psychological factors is implicated in the relationship between childhood sexual abuse and eating disorders. Wonderlich et al. report studies that have found significant associations between a history of childhood sexual abuse and disturbances in eating. They also note that "although the relationship of eating disturbances and other forms of child maltreatment has not received the amount of empirical attention seen in the childhood sexual abuse literature, there is evidence that eating disturbances may be linked to a history of childhood physical" abuse as well (1277–1283).